The distinction between Harpagochromis and Prognathochromis, and the distinction between these and other cichlid genera of Lake Victoria as proposed by Greenwood (1980), is demonstrated to be artificial. The BM(NH) collections of Haplochromis dichrourus and H. pellegrini were found to be polyspecific and are redescribed. On the basis of specimens formerly included in H. pellegrini a new species is described. Five new species are described based on material from the Mwanza Gulf and Maisome Island. Specimens of H. dichrourus from different areas of Lake Victoria are described separately to demonstrate geographic variation.